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Re: Safety FAQ is here -- draft, asking for comments.



Hi all,
        Following on from thoughts on arc growth, and Richard's 
reply....

<large snip
> All arcs make it, though, to the full length of the channel!!  Even the 
> weak ones! The weak one images are of reduced brightness, though.  The 
> arc channel is definitely pumped with ions which rise with the arc.  The 
> recombination time, even in air, is much longer than 2.5 msec. (seconds) 
> Thus, the arcs feed off of the previous arc channel's ions and zip 
> readily out to distances which, individually, they couldn't reach due to 
> Robert's comments about reduced cap energy along different parts of the 
> input sine.  As the arcs FIRST breakout, however, they are short, but do 
> feed on the last arc's energy and cause the following arcs to reach ever 
> greater and greater distances, until they either strike something or 
> until the channel has reached the limit of what constant pumping with the 
> limited energy of the system will support, in air.  A question that we 
> have never asnwered, is what causes the arc channel to hang on when 
> striking and then break when the energy is still pourin' in.  We have 
> lots of theories on this, but no definitve answers.  I think this is 
> where the terminal capacity comes in and relates to having "shot its 
> bolt" so to speak.  The "storage well" is empty.  Maybe the Ion load 
> (impedance) of a constant long time arc reaches the impeadance value of 
> the terminal load, and through voltage division, lowers the gap potential 
> over which the arc is jumping.  This would explain the FAILURE of new 
> arcs following the break from a long hot, sustained arc to restrike along 
> the same path, but look for another direction entirely!  Still, there is 
> no real proof of even this!

I think the hanging on has to do with a higher degree of ionization 
in the attached channel. The secondary is dumping its contents as 
fast as the primary is delivering. I have captured this happening on
the storage scope. The result in the time domain is a single (as 
opposed to multiple) beat envelope - in fact the beats disappear. In 
this condition, each primary cycle delivery of energy to the 
secondary is being lost from the secondary rather than being trapped
once the system voltage has risen high enough to turn a hot channel
into an extremely hot channel. The scope showed that several cycles
were required for secondary voltage to rise sufficiently at which 
point the output, instead of ringing all the way up was suddenly
attenuated and showed discharge artifacts (severe spiking). In fact, 
the system under these conditions has attained critical coupling (max 
power transfer).
     I think the attached channel stretches due to its rising by 
convection and eventually loses it due to the stretch becoming longer 
than the voltage needed to maintain it, whereupon a new one forms.
     Richard Quick's video shows this happening in graphic detail. 
You can see the frame-by-frame stretch occurring. 
     I am open to refutation of this view of things of course.

Regards,
Malcolm